Generally, when a visibility on a road is short to be 1 m due to heavy fog, the foggy situation threatens driving safety of a vehicle. When a driver drives a car in a situation such as heavy fog, heavy rain, and heavy snow, it is difficult to secure visibility and driving safety, which may lead to car accident. In order to prevent such a situation, as a measure to secure a clear view of a driver, vehicle applicable technologies which expand a viewing angle of the driver using a wide angle camera or a multi camera or notify the driver of dangerous situations which occur during the driving using a lane or obstacle recognizing sensor have been suggested. However, the technologies still have a difficulty to secure the visibility in a situation of fog, heavy rain, or heavy snow.
As an example of a safety driving system, Korean Unexamined Patent Application Publication No. 10-2011-0008126 discloses “Safe driving assistant system which is optimized for climatic environment to secure a viewing angle of a driver to the maximum.